1. Field of the Invention
The present invention is directed to a digital electronic still camera in which image data and sound data is recorded on and reproduced from a storage medium.
More particularly, the present invention is directed to a digital still camera which has data memory unit for recording DOS (Disk Operating System) information of image and/or audio files such as information describing a Bios Parameter Block, a file allocation table, and directory information.
The invention is further related to an efficient manner of processing the DOS information using a memory in the camera which has a smaller storage capacity than a memory card which stores the information. The invention is still further related to reading only a portion of directory information from the memory card to the memory of the camera.
2. Discussion of the Background
A digital still camera records image data and sound data on a storage medium such as a memory card and reproduces the images and sound from the storage medium. The image data and sound data is recorded on the storage medium which is formatted using an MS-DOS (Microsoft Disk Operating System) format, for example. The image data and sound data are stored and accessed using MS-DOS including DOS information such as information relating to a Bios Parameter block (BPB), a file allocation table (FAT), and a directory (DIR). Similarly, in a conventional personal computer, data stored using MS-DOS information is commonly utilized.
When MS-DOS information which is recorded on the storage medium in MS-DOS format is edited, the MS-DOS information is read out from the storage medium and is written in a data memory unit, also referred to as a data memory, installed in the personal computer. The MS-DOS information is edited in the data memory unit and is subsequently written in the storage medium.
If the storage medium with information stored using MS-DOS format has large memory capacity, the amount of MS-DOS information on the storage medium is increased. When a large amount of MS-DOS information is edited or changed, a large data memory is necessary. For instance, if the storage medium has a 12 MB capacity, the data memory for MS-DOS information is 64 KB. If the storage medium has a 24 MB capacity, the data memory for MS-DOS information is 128 KB.
However, the present inventor has determined that digital still cameras should have a compact design for ease of portability. A large data memory cannot be installed in the digital still camera in comparison with the personal computer. If a large data memory is installed in the digital still camera, the production cost for the digital still camera is also increased because the large data memory is expensive.